Device and method for application of radiation

ABSTRACT

A photonic scanning and delivery system capable of controllable transmission of light energy to an irregularly shaped treatment area are disclosed. The desired uniformity (controllability) of light energy application is ensured by a tracking device, which monitors the position of the radiation applicator and thereby prevents over- or under-radiation. The system employs a light energy delivery hand-piece. By these means, structures in the lower dermis are irradiated. Because of the large size of the treatment area, damage to surface tissue is avoided. The hand-piece can operate while in contact with the treatment surface. Treatment surfaces include non-medical work sites. Alternatively, the hand-piece can operate in a non-contact mode. The system can also be used in non-medical applications such as UV curing.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to devices that deliver uniform quantitiesof light energy to treatment surfaces.

2. Information Disclosure Statement

Light energy is used in a multitude and variety of industrial andmedical applications. For example, light energy may be employed for manycosmetic skin treatments including: 1) the removal of vascular lesions,benign pigmented lesions, and tattoos, 2) the abatement of blemisheswithin the lower dermis, 3) the removal of unwanted hair, 4) thecreation of skin pockets during hair transplantation surgery, and 5) theshrinkage of varicose veins. These applications typically require lightsources such as a pulsed dye, carbon dioxide, erbium, ruby, argon,alexandrite, copper vapor or Nd:YAG lasers. Additionally, diode lightsources such as laser diodes, frequency-doubled laser diodes, taperedlaser diodes, diode pumped solid state lasers, frequency-doubled diodepumped solid state lasers, diode pumped fiber lasers, or superluminescent diodes may be employed.

Most currently performed light energy (photonic) dermatology treatmentsinvolve either selective photothermolysis of pigmented structures withinskin or involve char-free vaporization of skin. Selectivephotothermolysis is the precisely controlled destruction of unwantedpigmented structures in the skin. This process avoids significant harmto overlying or surrounding tissue that might result in scarring.Pigmented structures targeted by this method typically include melaninparticles, enlarged blood vessels and tattoo ink particles. An operatorselectively heats targeted structures until they are photo-coagulated orphoto-disrupted, and the skin's natural physiological mechanisms breakdown and remove the light-altered remnants.

Selective photothermolysis removes tattoos by targeting the embedded inkparticles. A wavelength that is well absorbed by the ink particle breaksup the particle, and the remnants then slough off. The procedure mayrequire multiple wavelengths, depending on the number and kinds of inksused in the tattoo.

Hair removal is one of the largest potential markets for aestheticphotonic equipment and treatments. Hair removal methods rely onselective photothermolysis interactions with hair follicles. Althoughthe underlying mechanisms are not completely understood, they mostlikely depend upon the type of light source and specific methodemployed. In one method, a carbon-based ointment is rubbed into the hairfollicles. The carbon particles serve as the primary absorbers of lightenergy. In other “ointment free” methods, melanin particles lining thehair follicles are thought to absorb the light energy. The broadabsorption curve of melanin—the natural skin pigment responsible forskin's brown color—allows selective heating of subsurface melaninparticles by numerous visible and near-infrared wavelengths. Dependingon the patient's skin color (melanin content), however, some wavelengthsmay be more effective because they better penetrate overlying skin.

Another important example of a target tissue present throughout the bodyis the vasculature that contains erythrocytes. The erythrocytes containhemoglobin, a naturally occurring chromophore with a broad usableabsorption band in the visible region. The entire range of visiblewavelengths shorter than approximately 600 nm and extending into theultraviolet is available to purposely inflict damage to target tissuescontaining this chromophore. The specific wavelength selected dependson 1) the relative effects of scattering, which varies with wavelength,2) the presence of other chromophores, such as melanin, in the adjacentor overlying tissues, and 3) the availability of light sources.

The second major method of photonic dermatology treatment is char-freevaporization. In this method, certain types of light sources areemployed to vaporize soft tissue with little or no carbonization, whilealso controlling bleeding. These qualities afford practitioners a highlevel of surgical precision and control. Removal of upper skin layers inareas with wrinkles, acne scars or other blemishes usually results in“de-emphasized” wrinkles or blemishes after healing. During the healingprocess, the patient can use makeup to hide reddened skin (erythema),which can last for weeks or months after the treatment.

“Non-ablative” methods represent a fundamentally new way to resurfacethe skin. Instead of vaporizing upper skin layers, light energyselectively heats collagen fibrils in subsurface layers, whichstimulates the skin to make new collagen and “remodel” itself,de-emphasizing wrinkles. Selective heating of appropriate layers,several hundred microns below the surface may require simultaneousdeposition of a coolant to the tissue surface to prevent damage to theepidermis (Manni, Jeffrey G., Biophotonics International. Vol. 5 (3),1998, 40-7).

A method of applying coolant liquid to the skin surface to preventtissue damage was also described in U.S. Pat. No. 5,454,807, entitled“Medical Treatment of Deeply Seated Tissue Using Optical Radiation”,invented by Charles D. Lennox and Stephen P. Beaudet. The '807 patent ishereby expressly incorporated by reference as part of the presentdisclosure.

Simultaneous application of light energy and coolant in dermatologicalapplications allows greater amounts of energy to be transferred to thedermis without injuring the overlying skin layers. Coolant applied atthe treatment surface limits the elevated temperature range to themicro-vessels in the dermis to avoid any tissue damage and scarformation as a result of a dermatological procedure. The tissue surfacecan be cooled with a stream of fluid such as water, saline, and gaseousnitrogen, oxygen, or carbon dioxide.

In addition to simultaneous application of light energy and fluidmaterial, it often is advantageous to uniformly distribute light energyto a larger surface area, e.g. a surface area of 10 mm² or larger.Uneven distribution of light energy may lead to too much or too littleenergy at certain portions of the work or treatment site. This canrequire re-treatment that is costly, and subjects the patient or thework piece to an increased risk of scarring (damage) or other problemsthat may occur during the procedure. For example, epidermis receivingtoo much light energy may become charred and change colors, leading toabsorption of light energy destined for the dermis. Contrarily, if notenough light energy is applied to a site, the desired tissue change maynot be attained. These negative effects are often realized in manualtreatments because it is difficult to manually distribute energyuniformly. Thus, the skill of the practitioner in manual treatments haspreviously been of utmost importance for manually administeredtechniques.

In order to overcome the problems of non-uniformity of radiation,various scanning photonic delivery systems, typically incorporating acomputerized sub-system, have been suggested. For example, Ortiz et al.(U.S. Pat. No. 5,474,549) teach a system that provides for a uniformfluence level throughout a treatment site by scanning the light beam ata predetermined, controlled velocity (i.e. a controlled speed anddirection), and predetermined pattern. However, the problem with thisand other similar state of the art systems is that it is difficult totreat irregularly shaped areas that may be treatable by a manuallyoperated photonic delivery system. State of the art computerized systemshave a limited number of scan patterns, for example square, line,rectangle, rhombus, serpentine, triangle, or hexagon. Manuallycontrolled scanners, however, can be manipulated to an unlimited numberof scan patterns. An ideal laser scanning and delivery device,therefore, would offer the measured distribution of radiation of acomputerized system and the scanning flexibility of manually controlledsystems.

Additionally, computerized scanning systems can be very complicated,requiring intricate and expensive machinery. These systems may work wellfor a small two-dimensional treatment site, but may fail to treat largerthree-dimensional formed areas or surfaces that are more commonlyencountered in work and treatment applications. These three-dimensionaltreatment areas are commonly treated manually—a procedure inherentlydependent on the skill of the operator.

U.S. Pat. No. 4,733,660 describes a light energy delivery hand-piecethat provides an adjustable scanning mechanism that manipulates thedwell time of a focused light energy spot, thereby controlling the lightenergy absorbed by a target material. Specifically, the dwell time ofthe light energy beam is designed to match the thermal diffusion timefor destruction of the wall of an abnormal vessel, and some surroundingcollagen.

The Itzkan system of '660 fails to provide for a uniform distribution ofenergy throughout a work or treatment site. Moreover, it is difficult todetermine the thermal diffusion time for destruction of the wall of anabnormal vessel because it depends on relative effects of light energyscattering, which varies in the presence of chromophores, such asmelanin or erythrocytes in adjacent or overlying tissues. In exactly theconditions experienced in general application, the greatest problem withthe Itzkan system is present.

It is therefore the aim of the present invention to provide a manuallyoperated photonic scanning and delivery device that can delivercontrolled amounts of energy to sites, especially irregularly shapedtreatment or work sites.

OBJECTS AND SUMMARY OF THE INVENTION

It is therefore an object of the present invention to provide a manuallyoperated photonic delivery system that can controllably deliver lightenergy to a treatment or work site.

It is another object of the present invention to provide a manuallyoperated photonic delivery system that can uniformly deliver lightenergy to a treatment or work site.

It is yet another object of the present invention to provide a photonicdelivery system that may be manually maneuvered in unlimited patterns tobe especially applicable for if regularly shaped work or treatmentsites.

It is an aim of the present invention is to provide a photonic systemthat may be operated in contact or non-contact mode.

Briefly stated, the present invention provides a photonic scanning anddelivery system capable of controlled transmission of light energy to anirregularly shaped treatment area. The desired uniformity(controllability) of light energy application is ensured by a trackingdevice, which monitors the position of the radiation applicator andthereby prevents over-/under-radiation. The system employs a lightenergy delivery hand-piece. By these means, structures in the lowerdermis are irradiated. The hand-piece can operate while in contact witha treatment surface. A treatment surface includes non-medical worksites. Alternatively, the hand-piece can operate in a non-contact mode.The system can also be used in non-medical applications such as UV orlaser curing.

The above, and other objects, features and advantages of the presentinvention will become apparent from the following detailed descriptionread in conjunction with the accompanying drawings. Items illustrated indifferent figures that have equivalent numbers are substantiallyidentical.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates a preferred embodiment of the present invention shownin side cut cross sectional view.

FIG. 2 shows a further embodiment of the present invention displayingvisual output.

FIG. 3 depicts another preferred embodiment of the present inventiondisplaying visual output premised on FIG. 2.

FIG. 4a portrays the outer shell of the hand-piece of the presentinvention.

FIG. 4b illustrates the left-handed version of the outer shell shown inFIG. 4a.

FIG. 5 exhibits a further preferred embodiment of the present inventionemployed for hair removal.

FIG. 6 presents an embodiment of the present invention employed fordeposition of an adhesive film.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

The present invention provides a device for delivery of light energy toa work or treatment site. An embodiment of the present invention shownin side cut cross sectional view is illustrated in FIG. 1. Light energydelivery hand-piece, represented generally by 9, is employed to deliverlight energy to soft tissue treatment site 2. Application end 8 (tip) oflight energy delivery hand-piece 9 can be solid or hollow and ispreferably cylindrically shaped like a paint roller having approximatelya 1 cm diameter and 2 cm width, although it may be spherically shapedhaving approximately a 2 cm diameter.

The most critical property of the material used for application end 8 isthe transmission of pre-selected wavelengths with little or noscattering or absorption. For employment in applications with softmaterial sites, application end 8 ought to be a hard material, forexample, a perfluoronated plastic, made from a Teflon®-likefluoropolymer. Alternatively, for use in applications with hard materialsites, for example teeth, application end 8 should be a softer, morecompliant material. Polymers or elastomers with low hardness and hightransmissive properties, such as silicone, could be used. Applicationend 8 may be a lens itself in order to converge, diverge, or collimatethe light energy depending on a chosen application.

A material application sub-system can be integrated into the device toallow for simultaneous application of light energy and coolants, painrelievers, anti-bacterial agents, or other fluid material includingwater, saline, and gaseous nitrogen, oxygen, or carbon dioxide. However,unlike state-of-the-art systems, the present system can often be usedwithout coolants, because of the application tip location monitor, whichprevents over radiation.

In most applications, the cooling fluid materials preferably should besubstantially transmissive at the pre-selected operating wavelength andoptimally have a refractive index substantially equivalent to thetreatment material to reduce reflected light. However, in someapplications, it may be advantageous for an applied fluid material toabsorb some or all of the light energy. For example, for treatmentapplications, antibacterial agents may be activated by light energy, or,for non-medical applications, polymeric solutions may be UV-cured.

Again in FIG. 1, in a preferred embodiment, light delivery optics 3 hasrectangular shaped core that may provide optimal phase space for thelight energy. A rectangular core can maintain the brightness of theoriginal light source and thus allow maximum delivery of light energythrough application end 8. Additionally, by closely coupling the sizeand shape of the delivery fiber to that of the diode emitter, suitablepower densities may be maintained without increasing the output power ofthe emitter. Thus, smaller delivery fibers would make for more efficientdelivery of laser power at a specified density. As an alternative to arectangular fiber core, a standard round optical fiber may be employed.

During most applications, it is difficult to visually determine whichtreatment areas have previously been scanned. For example, in port wineapplications, the actual lightening of the lesion occurs slowly over aperiod of days to weeks as the body phagocytizes the necrotic tissue. Apreferred embodiment of the present invention includes a sub-system thatdetermines the position of application end 8 in relation to its startingpoint. This sub-system allows for greater controllability indistribution of light energy because an operator can recognize thepreviously treated areas and avoid applying additional radiation. Tofacilitate this, a three-dimensional positioning system, similar tothose currently used in multimedia virtual world applications in theentertainment field, is adapted for use in medical applications. Suchsystems determine the position of an object without contacting itssurface using supersonic acoustical waves or lasers. Such a system usedin a medical application offers the advantage of allowing the physicianto stop treatment and remove the hand-piece from the patient's skin, forcleaning, etc. and then replace the hand-piece. In an alternativeembodiment, the patient is also connected to a three-dimensionalpositioning system so that the patient's movement does not affect thetreatment parameters.

FIG. 2 illustrates an example of an embodiment where small cylinder 21is pressed against application end 22, corresponding to 8 of FIG. 1, sothat small cylinder 21 spins as application end 22 moves. The sub-systemcan be analogized to that of a common computer mouse. The sub-systemincludes opto-med encoded integrator 24 that transforms the movement ofsmall cylinder 21 into a digital signal that can be transmitted to unit25. Unit 25 is a monitor or computer coupled to a trigger. Thesub-system is programmed to recognize the position of the device inrelation to its starting point based on the distance traveled byapplication end 22.

In one embodiment, the dimensions of a regularly shaped work ortreatment site are input into the sub-system. Once a starting point ischosen, the subsystem determines which portions of the site have beentreated. If the treatment or work site is irregularly shaped, an outlineof the site can be mapped by starting the hand-piece at a point along anedge of the site and scanning the entire edge until the hand-piece is inits original position. This outline provides the boundary forapplication of light energy, and the sub-system will determine the areasthat have already received light energy treatment.

This sub-system ensures that each part of the work or treatment sitewill be treated only once with minimum overlap. In an embodiment of thepresent invention an acoustical signal is emitted by the sub-system toalert the operator if a region has been erroneously scanned.Alternatively a display unit is incorporated into the system thatemploys a color scheme to communicate to the operator which areas havebeen treated, and the quantity of light energy that has been applied toa certain portion of the site. This reduces operator error and the needfor additional treatment due to under or over exposure of a site.Furthermore, since operator error is reduced by this embodiment, lowerskilled people are able to operate it safely, particularly in emergencyoperation or for non-medical application of the invention.

In another embodiment, this sub-system is employed to regulate thedelivery of light energy as a function of treatment velocity (i.e. speedand direction). For example, if a power density of 10 watts/cm² ispre-selected by the operator, the system varies the power output (i.e.frequency of pulses for a system operating non-continuously, or dosagefor a system operating continuously) as the velocity of treatment isvaried. Higher powers are transmitted when the hand-piece is movedquickly, and lower powers are transmitted when the hand-piece is movedmore slowly. The ultimate effect is to transmit the same energy per unitarea, and thus provide for a uniform fluence.

Alternatively, it may advantageous to deliver different quantities oflight energy to different portions of a work or treatment site. Forexample, wound treatment will be more effective if a greater amount oflight energy is transferred to the center of the wound and a lesseramount to the outer regions of the wound.

State-of-the-art systems that can treat large three-dimensional sitescannot provide a controllable distribution of energy. Alternatively,state-of-the-art systems that provide a uniform distribution of energycannot treat a large three-dimensional surface. The above embodiments ofthe sub-system allow the present invention to be employed on a large,irregularly shaped, three-dimensional surface, while providing a uniformdistribution of energy.

At the edges of the applicator, channels 11 and 12 of FIG. 1, the edgesmay be designed to act as scrapers to remove dead skin and other debris.This feature provides for obstruction-free treatment areas.

The photonic delivery system may be activated by back-pressure onapplication end 8 of FIG. 1, or by an activation switch that may beintegrated onto the hand-piece. It is therefore not necessary to employthe system in contact with the work or treatment site Rather, the systemmay be operated in a “touchless” or non-contact mode. Additionally, forsafety reasons, the delivery system may be outfitted with a dead manswitch.

A touchless distance sensing system may be employed in connection withthe laser applicator hand-piece to allow for radiation to be appliedwithout contacting the work or skin surface. In an embodiment of thepresent invention, the laser applicator is held at a distance from theskin surface. A computerized distance sensor alerts the operatingphysician when the applicator is too far from the skin surface so thatthe physician may move the applicator into closer proximity to the skinsurface. The sensor also alerts the operator when the applicator is tooclose to the skin surface. A second distance sensor tracks the locationof the applicator in reference to its starting point and prevents theoperator from repeatedly scanning the same skin surface area. Therefore,areas may be effectively scanned without contacting the skin surface. Inan alternative embodiment, the patient is also connected to the sensingsystem to more accurately control the treated areas. Positioning systemembodiments of the present invention may operate using lasers orultrasound.

The “touchless” embodiment is particularly useful for employment insensitive treatment areas. For example, in wound treatment directcontact could further injure the treatment site. Furthermore, inphoto-activation applications where a sticky fluid substance haspreviously been applied at the treatment site, the use of the“touchless” hand-piece avoids complications that arise due to theadhesive properties of the fluid substance. A shaped application end(hand-piece tip) is not necessary for this embodiment, instead, anadjustable lens is employed in an alternative embodiment to focus,collimate or diffuse the light energy as required by the application.

The present invention system can be used to scan irregularly shapedsurfaces due to its position tracking capabilities. In FIG. 3, smallcylinder 21 is pressed against application end 22, corresponding to 8 ofFIG. 1, so that small cylinder 21 spins as application end 22 moves. Thesub-system includes integrator 24 that transforms the movement of smallcylinder 21 into a digital signal that can be transmitted to unit 25,which may be a display monitor or a computer and a trigger. Thesub-system can be programmed to recognize the position of the device inrelation to its starting point based on the distance traveled byapplication end 22. Here, unlike in FIG. 2, the treatment area isirregularly shaped.

FIG. 4a and FIG. 4b portray the outer shell of the hand-piece of thepresent invention. FIG. 4a is a right-handed piece and FIG. 4b is aleft-handed piece. Both hand-pieces have position tracking wheels,represented by 43 in FIG. 4a and 47 in FIG. 4b.

The present invention can be used with any chosen light source dependingon the application and wavelength desired. For example, indermatological applications the light source may be a pulsed dye, carbondioxide, erbium, ruby, argon, alexandrite, copper vapor or Nd:YAG laser.Additional light sources include, diode light sources including, but notlimited to, laser diodes, tapered laser diodes, frequency-doubled laserdiodes, diode pumped solid state lasers, frequency-doubled diode pumpedsolid state lasers, diode pumped fiber lasers, or super luminescentdiodes.

The light source can be integrated with the power supply unit, or canalternatively be a separate component, which may be interchangeable withother light sources. In another alternative, the light source could beintegrated into the hand-piece. For example, a diode light source couldbe integrated at the top of the hand-piece. In another alternativeembodiment, the present device may be employed with multiple lightsources having different wavelengths, thus allowing the operator greatercontrol of the depth of photonic penetration and subsequent blood vesselcoagulation. The desired light source module would be selected prior toapplying the radiation to the treatment surface.

There are numerous and varied applications that this device is suitablefor. For example, in hard tissue applications, hydrogen peroxide can besmeared onto teeth and then heated by light energy delivered through thehand-piece. This procedure can be employed to bleach the teeth and makethem cosmetically more attractive. The soft tissue applications of thepresent invention include, but are not limited to: 1) the removal ofvascular lesions, benign pigmented lesions and tattoos, 2) the abatementof wrinkles, scars and other blemishes, 3) the removal of unwanted hair,3) the creation of skin pockets during hair transplantation surgery, 4)the shrinkage of varicose veins, and 5) wound treatment.

FIG. 5 displays another embodiment of the present invention for use inhair removal. Lens 52 can be an adjustable lens to manipulate the spotsize required for certain applications. Hollow application end 54rotates around lens 52, which continuously remains in the sameorientation to light delivery optics 55, which may be a single opticalfiber or bundle of optical fibers. Light energy transmitted by lightdelivery optics 55 propagates through application end 54 and is focusedby lens 52 to hair follicle 51. The melanin within hair follicle 51absorbs light energy causing hair follicle 51 to coagulate and bedestroyed.

FIG. 6 provides an embodiment of the present invention employed fordeposition of an adhesive film. In FIG. 6, 62 represents a thin adhesivefilm. Lens 66 can be an adjustable lens to manipulate the spot sizerequired for certain applications, depending on the energy densityneeded. Applicator end 63 may be fixed with respect to light deliveryoptics 65, which may be a single optical fiber or bundle of opticalfibers. Light energy transmitted by light delivery optics 65 propagatesthrough application end 63 and is focused by lens 66 to film surface 67.The radiation is applied to photocurable adhesive compounds to createthin films.

The present invention may also be employed to create thin films at asubstrate site. For example, thin cross-linked hydrophilic polymericfilms can be produced. The present invention may be employed to smearthe solution on a substrate, and irradiate the site to activatecross-linking and polymerization. These films can be suitable forapplication as a carrier for biologically active agents, such aspharmaceuticals, both for humans and animals, insecticides, andfertilizers; as hydrophilic membranes for separation processes; asbandages for wound treatment; as body implants or as coatings for suchimplants; and as coatings on glass, metal, wood or ceramics.

Having described preferred embodiments of the invention with referenceto the accompanying drawings, it is to be understood that the inventionis not limited to these precise embodiments, and that various changesand modifications may be effected therein by one skilled in the artwithout departing from the scope or spirit of the invention as definedin the appended claims.

What is claimed is:
 1. A method of controllably applying radiation to anextended treatment surface comprising the steps of: selecting a lightsource having a wavelength which yields a desired depth of penetration;optically connecting said light source to a manually operated photonicscanning and delivery device; bringing said manually operated photonicscanning and delivery device to said extended treatment surface, saidsurface having an area substantially larger than an optical output beamof said delivery device; activating said light source; manually scanningsaid extended treatment surface with said scanning and delivery deviceto apply said radiation to a selected treatment area; employing amonitoring/measuring subsystem within said scanning and delivery device,which relays movement/position of said device to controllably deliversaid radiation from said light source in a predetermined pattern; andwherein said monitoring/measuring subsystem communicates to inform anoperator that a part of said extended treatment area has been treatedwith a quantity of a light energy from said light source to ensure thateach said part of said treatment area receives a desired amount of saidlight energy.
 2. A method of controllably applying radiation to anextended treatment surface according to claim 1, wherein said step ofbringing said device to said treatment surface involves bringing saidscanning and delivery device in contact with said treatment surface, andsaid manually scanning of said extended treatment surface is done in acontact mode.
 3. A method of controllably applying radiation to anextended treatment surface according to claim 1, wherein said step ofbringing said device to said treatment surface involves bringing saidscanning and delivery device in proximity to said treatment surface, andsaid manually scanning of said extended treatment surface is done in anon-contact mode.
 4. A method of controllably applying radiation to anextended treatment surface according to claim 1, wherein said step ofensuring optical connection to a selected light source involvesoptically connecting said device to a light source exterior to saiddevice.
 5. A method of controllably applying radiation to an extendedtreatment surface according to claim 1, wherein said step of opticallyconnecting said light source to a manually operated photonic scanningand delivery device involves selecting a light source module and placingit into said scanning and delivery device.
 6. A method of controllablyapplying radiation to an extended treatment surface according to claim 2wherein said step of monitoring/measuring subsystem measures location bya contact mode employs a technique selected from the group consisting ofa spinning cylinder/sphere, supersonic acoustical waves and lasers.
 7. Amethod of controllably applying radiation to an extended treatmentsurface according to claim 3, wherein said monitoring/measuringsubsystem measures location by a non-contact mode employs a techniqueselected from the group consisting of supersonic acoustical waves andlasers.
 8. A method of controllably applying radiation to an extendedtreatment surface according to claim 1, wherein saidmonitoring/measuring subsystem communicates to an operator by anacoustical signal.
 9. A method of controllably applying radiation to anextended treatment surface according to claim 1, wherein saidmonitoring/measuring subsystem communicates to an operator by a displayunit that employs a color scheme.